US1454972A - Burner for internal-combustion engines - Google Patents

Description

May 15, 1923. 1,454,972

E. L. LOWE BURNER FO R INTERNAL COMBUSTION ENGINES Filed Dec. 29. 1922 2 Sheets-Sheet 1 ATTORNEYS.

May 15, 1923. 1,454,972

E. L LOWE BURNER FOR INTERNAL COMBUSTION ENGINES Filed Dec. 29. 1922 2 Sheets-Sheet 2 ATTORNEY? nary fuel oil.

Patented May 15, 1923.

UNITED STATES EDWARD L. LONE, OF PALO ALTO, CALIFORNIA.

BURNER FOR INTERNAL-COMBUSTION ENGINES.

Application filed December 29, 1922. Serial No. 609,777.

To all "whom it may c0n0cm Be it known that I, EDWARD L. Lowe, a citizen of the United States, residing in the city of lalo Alto, county of Santa Clara, State of California, have invented a new and useful Burner for Internal-Combustion Engines, of which the following is a specification.

My invention relates to a novel construction of a burner and its adjuncts for inter nal combustion engines, whereby in lieu of gasoline as a fuel I am enabled by my novel construction to employ the cheapest and heaviest grades of hydrocarbons or oils whose cost approximates but a few cents per gallon, as compared with the more expensive lighter hydrocarbons, such as gasoline and the like. a

In order to describe my novel burner for oil burning internal combustion engines, I will give certain fundamental facts and requirements with respect to the combustion of fuel oil which form the basis of this invention.

(1) At the present time ordinary internal combustion engine; fuel. oil has generally a flash point between 150 F. and 200 F. and a tire testin the neighborhood of 250 F. or 300 F.

(2) Air when compressed to 200 pounds per square inch gauge is raised in temperature to about. 670 F. Lower as well as higher compressive pressures have corresponding temperatures. It will be noted that'the temperature of 670 is far in excess of that actually required to burn ordi- If now this temperature can in some way be utilized. to ignite oil of combustion, a new era in internal combustion engine construction will be inaugurated.

My novel burner which is the subject of this application comprises a device which may be used on engines with compressive pressures lower than those used in engines of the Diesel type and is applicable to engines using a light fuel for starting only, as well as engines which have no such provision, depending in either case entirely upon the compressive pressures for which the engineis designed. My experiments have indicated that with a compressive pressure of about 200 pounds per square inch, ordinary fuel. oil may be ignited from a cold start and that an engine with much lower compressive pressure will operate satisfac- Extremely high temperatures as met with in the hot bulb engines have a tendency to decompose or crack the oil of combustion instead of vaporizing it and with consequent deposition of carbon. When the oil of combustion deposits oncool surfaces it does not vaporize and ,a carbondeposit results.

To the above ends my invention consists of a novel construction of a burner for internal combustion engines comprising a pinrality of concentrically arranged cylindrical metallic ferrules, thimbles or sleeve-like members which for convenience of manufacture are made separate so as to be readily assembled orv disconnected if desired, said thimbles being clamped or positioned by novel mechanism within a pocket or passage in the engine cylindercommunicating with the compression chamber.

It further consists of a novel construction of a burner for an internal combustion engine composed of an outer flange or supporting member, a pluralityof concentric metallic conical thimbles, ferrules or sleevelil're members so collocated that a conical central combustion chamber of relatively large area is provided within the inner thinible, while the conical space between the two thimbles comprises a thin or restricted annular ignition chambelm It further consists of a novel crmstruction of a burner composed of. flaring. concentric thimbles or sleeve like members. which are in the shape of truncated cones whose largest areas are at the bottom, the inner thimble being preferably shorter than the outer thimble and novel means being provided for positioning said'burner in a passage in the engine cylinder in communication with the compression chamber.

It further consists in combinationflwith erated valvular member, which is seated by back pressure from the burner, said valve being enclosed within a bonnet carried by a casing, whose base flange also serves to clamp the elements of the burner in position with respect to its pocket in the engine cylinder.

It further consists of a novel valvular device, a novel burner having a downwardly flaring central combustion chamber and a thin, outer, conical, restricted, downwardly flaring, ignition chamber, and novel means for assembling these devices with respect to the engine cylinder.

It further consists of other novel features of construction, all as will be hereinafter fully set forth.

For the purpose of illustrating my invention, I have shown in the accompanying; drawings, a form thereof which is at present preferred by me, although it is to be understood that the various instrumentalities of which my invention consists can be variously arranged and organized and that my invention is not limited to the precise arrangement and organization of these instrumentalities as herein shown and described.

Figure 1 represents a vertical, sectional view of a burner and fuel oil regulating device, embodying my invention.

Figure 2 represents on an enlarged scale in detached position, a perspective view of the outer thimble, ferrule or sleeve-like member, of the burner.

Figure 3 represents on an enlarged scale in detached position a perspective view of an inner thimble, ferrule or sleeve-like member, which is adapted to be inserted into the construction seen in Figure 2 to form the burner.

Figure 4 represents on an enlarged scale in detached position, a vertical sectional view of a fuel control valve, showing its ports and hollow guiding means.

Figure-5 represents in detached position, a perspective view of the spring, head and stem which control the admission of the fuel.

Figure 6 represents on an enlarged scale a vertical sectional view showing the base flange of the valve casing, t e top of the engine cylinder, the flange of the outer burner in'embera'ndthe manner of forming a tight joint between these elements, whereby a single gasket effects the packing of these devices.

Similar numerals of reference indicate corresponding parts.

Referring to the drawings,

1 designates the engine cylinder and its water jacketed cylinder head and 2 the piston therein, which has its upper wall 8 preferably rounded or convex, the juxtaposed wall 4; of the piston chamber 5 being preferably of the same contour as said piston end 3. The cylinder has the passage 6 in its upper portion and the air inlet 7 leading to the chamber 8, communicating with said passage, which is controlled by the air intake valve 9. The exhaust chamber communicating with the passage 6 is indicated at 10, and is controlled by the exhaust valve 11, the exhaust escaping through the pipe 12.

My novel engine has no spark plugs and the valves 9 and 11 and the piston 3 are actuated by any suitableor conventional mechanism, which it is unnecessary to describe in detail.

'13 designates a passage or pocket in the top of the cylinder in which is positioned the burner 14 composed of a plurality of metallic ferrules, thimbles or sleeve-like members, which with their adjuncts con stitute the salient features of my invention and will now be described, said burner extending towards the compression space and. having its end opening thereto.

The burner is composed of the outer member 15, which comprises a flange 16, having the circumferential bottom shoulder 17, see Figure 6, which rests on the upper wall or edge of the pocket 13, the outer edge of said flange being beveled as at 48, (see Figure 6) and resting upon the gasket 18, which also contacts with the bevelled wall 49 of the flange 29, to be hereafter referred to. From the flange 16 depends the hollow, open ended, conical thimble, ferrule or sleeve-like member 19 having the shape of a truncated cone, whose diameter in cross section gradually increases downwardly and is preferably largest at its lower end 20.

21 designates an inner circumferential shoulder within the flange 16, upon which rests the outer peripheral portion of the flange 22, from which depends the inner conical thimble, ferrule or sleeve-like member 23, which is of the shape of a truncated cone, whose diameter gradually increases downwardly, the bottom edge 24 01? the member 23, preferably terminating a s'hort'distance above the bottom 20 of the outer sleeves 19 and. 23, and the inner central flaring combustion chamber 27, is contained within the inner conical sleeve It will be seen front the foregoing that the conical sleeves l9 and23, whose'individual construction will be understood from Figures 2 and 3, when assembled as seen in Figure 1, form a unit .or burner 14: comprising the central flaring combustion chamber 27 of relatively large area flaring downwardly and the outer conical thin or restricted ignition chamber 26, which also flares downwardly and discharges into the lower end of the outer sleeve 19, it being also apparent that the lower portion of the passage or pocket 13, in which the burner is positioned, also flares downwardly to meet the wall 4, as indicated at 28. The burner or unit 14 is clamped in position by i means of the base flange 29 of the valve casing 30, said flange being secured to the cylinder by bolts or the like 31, and by reason of the gasket .18 being positioned as seen in Figure 6, the requisite tight joint between the various elements can be obtained by the employment of a single gasket.

32 designates the fuel inlet pipe for the admission of liquid fuel, which is secured to the extension 33 by the coupling 34, said extension projecting from the bonnet 35, which is secured within the valve casing by the couplingnut 36, whose upper inner portion bears on the bonnet flange 37. The upward extension 33 ofthe bonnet 35 has the upper port 38, which admits the fuel upon the top of the valve 39, having the ports 46, said valve havingthe pendant hollow guide '40, having the internal upper shoulder 41, see Figure 4. The upper end of the spring 42 bears against said shoulder ll and its lower end bears on the head 43, whose bottom is conical and rests on a conical seat above the flange 29, said headhaving the ports 44: therethrougln which communicate with the port 1-7 which admits the fuel directly into the combustion chamber 27. From the head 43 projects the stem 45 which is surrounded by the spring 42, the tendency of said spring normally being to seat the valve 39 upwardly, as seen in Figure 1, I

It will be seen from the foregoing that not only the burner and its adjuncts canbe readily assembled and disconnected for the purpose of inspection, replacement or repairs,

but the fuel. control valve and its adjuncts are alsoreadily accessible, by the manipulation of the coupling nut 36.

WVhile I have shown in Figures 1, 2 and 3, the preferred manner of constructing and assembling the burner elements 19 and 23 with respect to the base flange 29, it will be evident that these elements may be differently constructed and assembled. It is, however, essential that the burner elements 19 and 23 be of relatively thin metal and that they be attached to or at least in metallic contact is not so susceptible to quick changes of temperature, as are the thimbles or'burner elements 19 and 23, as will be hereafter 6X- plained.

The operation is as follows in a two cycle t engine.

In order to start it is only necessary to set the engine in motion or turn it over either by hand or by any one of the conventional methods now in use, and in the following description the term inward refers to the motion of the piston towards the crank shaft,

space 13 relinquishes a portion of its heat to the jacket water through the cylinder head wall 4, and a portion to the thimble or outer burner element 19, and also a portion to the cap or flange 29. In like manner the air in the space or ignition chamber 26 relinquishes heat to the thimbles or burner elements 19 and 23, and to the thick base flange or cap 29. The air inthe combustion chamber or space 27 relinquishes heat to the thimble or inner burner element 23 and also to the cap or flange 29 which latter also receives heat from said, burner elements 19 and 23, by reason of its direct contact therewith.

As the piston moves inward after the first compressive stroke, the compressed air expands losing its heat and the air in the spaces 1.3, 26, and 27, while cooling obviously re ceives heat from the thimbles or burner elements 19 and 23 and from the cap or flange 29, which elements being made of metal lose their heat less rapidly than the air. ld hen "the piston reaches the end of its inward stroke and a fresh charge of air enters and it moves outward again on its second compressive stroke, the burner and air within it are still warm, so that the interchange of heat between the burner and the compressed air will be less than on the first stroke, but

interchanges of heat take place in a similar 1 manner. On the third stroke, the interchanges will be less than on the second, and so on until the burner reaches a temperature approaching that of the air of compression. When this point has been reached, a change of fuel is allowed to enter the burner through the port or aperture a7. The oil first appearing at the mouth of the opening 47 initially receives heat during its passage through and contact with the cap or flange 29 and from air inthe space or central com bustion chamber, 27. The heat given up by the air is immediately made up in part by radiation from the inner burner element or thimble 23, and cap 29, and is suliicient to vaporize and ignite the charge, which is supplied by a piston pump to the inlet- 32 and its discharge into the burner continues over a fixed period of the cycle. The oil, therefore reaching the burner after the initial flash burns upon its arrival within the burner and burns completely leaving no residue or carbon deposit. In fact, no oil reaches the combustion space of the cylinder except in an incandescent state.

It will be readily appreciated that the ignition and burning of the charge materially alters the heat interchanges that take place subsequent to ignition. The thin. burner elements 19 and 23 are heated to a temperature in excess of that corresponding to the compressive pressure and in consequence upon each successive compressive stroke, instead of receiving heat from the air of compression, they give up heat to it, or in other words, they are cooled by the air of compression. My novel burner therefore functions to maintain a reasonably even temperature, the design thereof being such as to lend itself to this desired end.

It will be noted that the base flange or cap 29 is of heavier metal than the thin burner elements 19 and 23, which are in contact with it. The cap element 29 is there fore not so susceptible to quick changes of temperature as are the thimbles or burner elements 19 and Q3, and thus acts a temperaturc regulating member. During the combustion stroke, this is a vital matter. as it is the only means provided to keep the thimbles or burner elements below destructive temperatures. The fact that my novel burner functions without overheating uncer all conditions of load or revolutions indicates that the heat balance is reached which fulfills all requirements. From the foregoing it will now be apparent that should it be desired to use a compression pressure lower than that required to ignite low grade fuel oil by compression when the engine is cold. a lighter fuel oil with higher flash and tire test may be used for starting, and after the burner has received heat from combustion, the light oil may be shut off and the lower grade oil turned on to the burner. It will then continue to function on the low grade oil receiving and dispensing heat as described above.

It will be understood from the foregoing that the thin conical ignition chamber 26 and the central conical relatively large combustion chamber 27 are always filled with air during the period of compression. At or near the end of the. compression stroke, fuel is slowly admitted through the passage 47 into the heated air due to compression contained in said combustion 27. Due to the natural action of liquid fuel when subjected to heat interchanges causing a partial cracking or separation of the lighter and heavier gases, the lighter gases naturally rise to the top of the combustion chains ber 27, and the heavier gases remain suspended below the lighter gases in said combustion chamber which now contains a fuel which has slowly been admitted, and due to heat interchanges has become gasified to a greater or lesser degree, and is now com' mingled with the air in the combustion chamber heated by compression, which has caused the heat interchanges between the thimbles and cap. as above explained.

As stated the lighter gases are now at the top of the combustion chamber due to natural causes. Also due to the fact that the lighter gases will ignite at a much lower temperature than the heavier gases, the series of ports 25, at the top of the combustion chamber 27 connecting with the outer thin ignition chamber 26, allow the lighter gases when they begin to ignite to come into contact with the pure compressed air in said ignition chamber, and said pure air in the ignition chamber accelerates the burning of said lighter gases, which causes a very quick interchange of heat upon thethimble or burner element 23 surrounding the combustion chamber 27. There is no explosion in my novel device at any stage of the cycle, but instead a slow progressive burning due to the fact that the oil is slowly admitted, the initial burning taking place in proximity to the ports 25, and a portion of the initial flame is in the upper part of both the ignition chamber and the combustion chamber. The burning of the gases progresses gradually downwardly and reaches the mouth of the burner communicating with the compression space of the cylinder, and the burning gases come in direct contact with the heated air in the compression space which causes a complete combustion of the gases above the piston, which in turn effects the actuation of the latter. The manner of exhausting the cylinder does not require special mention, the exhaust taking place through the passages 6, 10 and 12, and being controlled by the valve 11 operated by any conventional means. Especial attention is called to the coaction of the thickened cap 29, with the burner elements since its prime function is to absorb heat from the thin thimbles or burner elements during the combustion stroke, and thus reduce the temperature below the burning point.

The valvular mechanism seen in Figure 1, can be dispensed with if desired, and the fuel fed directly to the port 47, under which conditions the burner and its'adjuncts will function perfectly.

I prefer under certain conditions and with certain grades of fuel to employ the valvular arrangement shown, wlierein it will be apparent that the valve 39 will be unseated downwardly Whenever the pressure in the pipe 32 is suflicient to overcome the tension of the spring 42, in which case the fuel will flow through the ports 46 and 44 to the passage 47 which I have shown as terminating in a nozzle in proximity to the ports 25, which nozzle may be omitted if desired.

It will be apparent that any back pressure in the burner or combustion chamber 27 will tend to seat the valve 39 upwardly, this upward seating tendency being augmented by the spring 4:2, as is evident.

l/Vhile I preferably proportion the lengths of the burner elements substantially as seen in Figure 1, and have shown them as being conical or flaring my device will function satisfactorily if concentric cylinders are employed, and if said burner elements re of substantially the same length.

I have found from an extensive practical use of my novel burner under all conditions and with varying grades of fuel that a greater efliciency is attained by the employment of the thin conical or flaring burner elements 19 and 23, whose lengths are pro portioned substantially as shown, and I also in conjunction therewith employ the flaring mouth 28, which flaring constructions cause or enable the flame or expansive effect of the burnt gases somewhat to. diverge and impinge substantially instantaneously upon the entire juxtaposed end area 3 of the piston, so that substantially every portion thereof receives the effect of the burnt gases. For this reason, one standard size of my novel burner composed of the flaring or conical burner elements 19 and 23 can be utilized as the burner unit for engines or pistons of a relatively wide range of sizes or diameters, as is evident.

Obviously, a plurality of burners 1% may be employed to a single cylinder, and when a pluralityof saidburners are employed, it will be evident that they may be disposed around or in the cylinder head in any desired arrangement which will produce the greatest efficiency. Additional thimbles may also be employed if desired. f

While I preferably make the inner thimble somewhat shorter than the outer thimble, it will be apparent that the lengths ofthese thimbles may be proportioned differently from the construction shown, it being essential, however, that the central combustion chamber and the outer ignition chamber communicate at their upper and lower portions, the'upper. communication being had by the restricted ports 25'. V I

My. present invention 1s diflerentlated from the burner shown in my. contemporaneously pending application, Serial No. 537,997, since the outer thimble. or sleeve herein is open throughout its entire lower area and flaring, as is also the inner thimble,

which facilitates the discharge of the expansive medium upon the juxtaposed end of the piston, as is evident.

It will now be apparent that I have de vised a new'and useful burner for internal combustion engines, which embodies the features of advantage enumerated as desirable in the statement of the invention and the above description, and while I have, in the present instance, shown and described a preferred embodiment thereof which will give in practice satisfactory and reliable results, it is to be understood that such embodiment is susceptible of modification in various particulars without departing from the spirit or scope of the invention or sacrificing any of its advantages.

Having thus described by invention, what I claim as new and desire to secure by Let tors Patent, is

1. In a device of the character stated, a burner composed of an outer sleeve, an inner sleeve positioned within said outer sleeve, both of said sleeves being open and unobstructed at their lower ends, and flaring and of gradually increasing diameter in cross section, whereby a flaring ignition chamber is formed between said sleeves open at its bottom and a relatively large flaring combustion chamber is formed within said inner sleeve, said chambers being in communication at their upper and lower ends.

In a device of the character stated, a

burner composed of an outer conical sleeve,

and an inner conical sleeve of less length than said outer sleeve positioned within said outer sleeve, whereby a relatively thin outer conical ignition chamber open at its bottom is formed between said sleeves and a rela tively large central conical combustion chamber is formed within said inner sleeve, the latter having ports at itsupper portion forming a communication between the up per portions of said chambers and both of said sleeves being open and unobstructed throughout the entire area of their lower ends.

3. In a device of the character stated, a burner composed of an outer conical sleeve, and an inner conical sleeve positioned within said outer sleeve, and having its lower end terminating above the bottomof said outer sleeve, whereby a relatively thin conical ignition chamber open at its bottom is formed between said sleeves, and a relativelylarge central conical combustion chamber is formed Within said inner sleeve, the latter having ports at its upper portion forming a communication between the upper portions of said chambers and said outer sleeve being open and unobstructed throughout its entire area at its lower end and a fuel nozzle discharging fuel into sald combustion chamber at a point in proximity to said ports.

-1-. In an insertiblc burner for internal combustion engines, an elongated central conical combustion chamber and an elongated surrounding relatively thin conical ignition chamber communicating.therewith through restricted ports near its upper portion, the remaining portion of said elongated ignition chamber being cut off from said combustion chamber, but communicating therewith at its lower end, said chambers being open and unobstructed throughout their entire lower area opening into the compression space.

A burner for engines of the slow combustion type, comprising a plurality of approximately concentric, conical sleeves separated from each other by an outer conical air space forming an ignition chamber opening into the compression space of the engine and a central conicalcombustion chamber formed within the inner-sleeve and opening into said compression space and having restricted communication with said conical ignition chamber near one end, the opposite ends of said chambers communicating and the outer conical sleeve being open and unobstructed throughout its entire lower area opening into said compression space.

(3. An insertible burner for internal combustion engines, comprising a plurality of interfltted conical sleeves, one within the other, and separated from each other by an outer elongated conical air space forming a relatively thin ignition chamber, the inner sleeve containing the, conical combustion chamber and having small ports at its up per end, saidburner being adapted to be mounted in the wall of an engine cylinder, and said combustion chamber and ignition chamber communicating at their lower ends and opening into the compression space of said cylinder. said chambers being non-communicating throughout their length and open and unobstructed at their lower ends, and a support 'for said sleeves adapted to be secured to said cylinder.

'7. in a device of the character stated, a burner composed oi an outer conical sleeve and aninner conical sleeve positioned within said outer sleeve, both of said sleeves being open and unobstructed at their lower ends, whereby an outer conical ignition chamber is formed between said sleeves open at its bottom, and a relatively large conical combustion chamber is formed within said inner sleeve, said chambers being in communication at their upper and lower ends, in combination with a relatively thick cap in metallic contact with the upper ends of said sleeves, for securing the latter in po sition. V

8. In a device of the character stated, a burner composed of an outer conical sleeve and an inner conical sleeve positioned within said outer sleeve, both of said sleeves being open and unobstructed at their lower ends, whereby an outer conical ignition chamber is formed between said sleeves open at its bottom, and a relatively large combustion chamber is formed within said inner sleeve, said chambers-being in communication at their upper and lower ends, in comination with a relatively thick cap in metallic contact with the upper ends of said conical sleeves, said cap having a chamber therein for the reception of a liquid and an opening therethrough for the admission of the fuel.

9. The combination of an engine cylinder, a hollow cap secured theretoand adapted to receive a liquid and having a fuel passage therethrough, a plurality of flanges in metallic contact with said cap and secured to said cylinder thereby, an outer conical thimble carried by one of said flanges and positioned in a passage within said cylinder, said outer thimble being open and unobstructed at its lower end, an inner conical thimble secured to the other 01" said flanges and positioned within said outer thimble, whereby there is formed a central conical combustion chamber and an outer conical ignition chamber, said chambers being in communication at their opposite ends, and both of said chambers having an uninterrupted communication at their lower ends with the compression space of the cylinder.

10. The combination of an engine cylinder, a relatively thick cap secured thereto and having a fuel passage therethrough, an outer flange in metallic contact with said cap and having a conical thimble secured thereto and open and unobstructed at its lower end, and. an inner flange seated in said outer flange and in metallic contact with said cap, an inner conical thimble carried by said flange and positioned within said outer thimble, and ports near the upper end of said inner conical thimble, there be ing a conical combustion chamber formed within said inner thimble and a conical ignition chamber formed between said thimbles, said chambers communicating at their bottoms.

11. A burner. for an internal combustion engine, formed of an outer flange, an outer conical thimble secured at one end thereto and open and unobstructed at its. opposite end, a counterbore in said outer flange, an inner flange seated in said counterbore and an inner conical thimble having ports near its flange end, secured to said inner flange and positionedwithin said outer thimble.

12. A burner for an internal combustion engine, formed of an outer flange, an outer conical thimble secured at one end thereto and open and unobstructed at its opposite end, an inner flange seated in said outer flange and an inner conical thimble secured to said inner flange and positioned within said outer thimble and having restricted ports near its flange end, said inner thimble being shorter than said outer thimble.

13. A burner for an internal combustion engine, formed of an outer flange, an outer conical thimble secured at one end thereto and open and unobstructed at its opposite end, an inner flange seated in said outer flange, an inner conical thimble secured to said inner flange and positioned Within said 1 outer conical thimble, and having restricted ports near its flange end, said inner thimble bein shorter than said outer thimble, and a re atively thick cap in metallic contact with said flanges for securing the latter to an engine cylinder.

14. The combination with an engine cylinder, of a burner flange supported thereon and having an inward bevel. on its under side, a clampin member in metallic contact with said ange, and having an out wardly inclined bottom bevel juxtaposed to said inner bevel, so as to form an annular angular seat, a gasket supported between said cylinder and angular seat, and hastening devices common to said clamping member and cylinder for compressing said gasket.

15. The combination with an engine cylinder of a burner flange supported thereon, a plurality of pendant hollow burner elements supported from said flange, the latter having an inward bevel on its underside, a

clamping member in metallic contact with said flange, and having an outwardly inclined bottom bevel juxtaposed to said inner bevel, so as to form an annular angular seat, a gasket supported between said cylinder and angular seat and fastening devices common to said clamping member and cylinder for compressing said gasket.

16. A metal burner for internal combustion engines, comprising a plurality of ap proximately concentric thimbles separated from each other by air spaces, a heavier member holding said thimbles in position and in metallic contact therewith, said member serving as a temperature regulator, whereby heat interchanges between said thimbles and member take place by their metallic contact and said thimbles are kept below destructive temperatures during the combustion stroke.

EDWVARD L. LOWVE.

lVitnesses H. S. FAIRBANKS, C. D. MCVAY.

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